Yes, Cloud-Init does support Windows containers in Proxmox, but additional configuration is required to enable Cloud-Init for Windows. Unlike Linux, Cloud-Init is not natively supported on Windows, so additional software and configuration are needed to make it work. One popular tool for enabling Cloud-Init support in Windows is Cloudbase-Init, which is an open-source tool that provides a Windows implementation of the Cloud-Init tool. With Cloudbase-Init, you can use Cloud-Init to automate the setup and configuration of Windows containers in Proxmox.
To enable Cloud-Init for Windows containers in Proxmox using Cloudbase-Init, you need to install Cloudbase-Init in the Windows container and configure it with the necessary settings, such as the hostname, administrator username and password, and any additional scripts or commands that you want to run during the setup process. You also need to create a user-data file in YAML format that contains the Cloud-Init configuration settings and add it to the Proxmox container configuration. Once everything is set up, Cloud-Init will automatically configure the Windows container based on the specified settings and scripts.
It's important to note that the level of support for Cloud-Init in Windows is not as advanced as it is for Linux, and some features may not be available. However, Cloud-Init can still be a useful tool for automating the setup and configuration of Windows containers in Proxmox, and it can save time and reduce errors in the configuration process.